Oysters are
two-shelled mollusks that mostly live off the coast of Southern Sarvonia. They
may be found as far northward as the Bay of Sky, but are most common in the
Yanthian Gulf and the Gulf of Maraya. They prefer temperate salt water, and
attach themselves to underwater coastal rocks where food is brought to them by
the constant motion of the waves.

Appearance.
Oysters have a blackish ovoid pebble-shape, slightly narrower on one end of the oval, and
flattened in a smooth curve at the other. The two hard shells that form each
side of the oval are fringed with a greenish-black substance which helps to
protect the sensitive pale flesh of the interior. Usually the shells are about a
nailsbreadth open, so that water and dissolved food particles can filter through
the digestive membrane.

These finger-long mollusks are also known as "sisters" - a clever
double pun, from the Styrásh "sýs"
(sýs), meaning "two",
referring to their bivalve shells, and also a reference to the fact that they
are always found in groups together. They are also often referred to as
"Two-Shells" or "Pearl-Houses".

The two shells are held together by a strong muscle, and edged by a membranous
mantle, which contains primitive sensory organs and helps the oyster respire.
The interior is coated with nacre, or "pearl-father", a shining
iridescent substance, which protects the tender animal inside. Any grit that
makes its way past the delicate fringe that edges the shell openings is also
coated with pearl-father and eventually turns into a pearl itself. The oyster
also secretes a powerful mucus which allows it to "glue" itself to rocks,
coral, packed seabed, or other mollusks.

Special Abilities.
The Oyster's most famous ability is of course the secretion of nacre, which it uses to
create pearls around any small bits of irritation that make their way inside the
Oyster. Various sorts of Oysters prefer various depth and currents of water, and
the Avennorian pearl harvesters have become experts on the best location for the
most likely formation of large pearls.

Though the Oyster has no other abilities that strike any as utterly fascinating,
many are amazed that this creature still exists even though it has no eyes,
ears, or nose, hindering it from the senses of sight, sound, and smell. It
survives solely by using its two rows of feelers that help it to sense and respond to
changes in its environment.

Territory.
Oysters prefer warm, saltwater environments in temperate climates. They thrive
on the coast of Southern Sarvonia where the
Avennorian people feast upon them.
They are collected in enormous quantities on the Yanthian Gulf and the Gulf of
Maraya. However, even those living near the Herrings Bay and the Aetryam Sea
have also collected them, though not the vast amounts the
Avennorians record.
There have been accounts of these shellfish being found further northwards, but
they are usually only found there during hot years. There have been a few attempts to
cultivate Oysters, for the purpose of introducing irritants into their shells
and thus creating more pearls, but these are so far only in the experimental
stage and are not yet commercially viable.

Habitat/Behaviour.
Oysters are rather timid creatures but, though independent, will live near each
other on the same rocks or coral. They spend the majority of their lives tucked
away within their rough shells. The average lifespan of an Oyster is about 6
years, though some may live as long as 20 years.

Diet.
The Oyster is a filter feeder, depending on the constant motion of the oceans
to bring it tiny pieces of algae and other substances it needs. The Oyster feeds by opening its
shell as each new wave rushes over it, and taking some of this nutritious
seawater into itself. From there it filters the nutrients out of the water
before spitting it out into the ocean again. The inevitable bits of sand and
other indigestible irritants which the Oyster fails to filter eventually develop
a coating of pearl-father and become the lovely nacreous jewels of the sea with
which we are familiar.

Mating.
In early to mid spring, mating begins. Mating, for Oysters, is a rather
haphazard process. The males simply eject a greenish fluid which spreads out
around them with the movement of the water, and any female Oysters in the area
will receive it as they have their shells open to feed. This fluid seems to have
a surprisingly long period of viability, retaining potency for up to a week,
during which time it can be spread widely by the currents and waves.

The female, after having been fertilized, will produce anywhere from five
hundred to one million eggs within the year. These eggs are yellow in color and
are so small that, when bunched together, resemble thick yellow cream. These
eggs hatch after about 10 hours and, within a day of their hatching, will have
begun to grow a shell.

The first weeks of the Oyster’s life is spent swimming or floating in the
dangerous sea waters where many young Oysters fall prey to fish, crabs, and
other such creatures. The young Oysters grow a “foot” to help them avoid
attack by predators that can still break through the undeveloped shell. Once the
Oyster has found a place to settle, it attaches itself firmly to that place with
its strong mucus, and its shell begins to harden rapidly. These shellfish tend
to collect together in groups called "beds", and will rarely move from a
bed after having settled.

Young Oysters grow at an alarming pace. Though they are hardly more than three
or four grains across after the first month, they will grow to be two and a half
nailsbreadths in diameter within the years, and from there will grow about two
nailsbreadths a year for three or four years. Even after these first few years
of growing, though, they will still continually grow and may expand to become
little less than a fore! Such Oysters are extremely rare, though.

Usages.
Oysters are mostly desired for the pearls that they produce, and the Avennorians
have made a virtue out of harvesting the sea-gems. However, they have also
discovered that the tender flesh of the Oyster is edible, and not wanting to
waste food, have made it a part of their diet.

Oysters can be roasted in their shells, fast-fried, deep-fried, or smoked. A
couple of inventive mages have experimented with sealing the beasts' shells in
an attempt to preserve the meat for transport, but there is no current market
for Oysters. As yet Oyster meat is not regarded as a delicacy inland, and the
fisher folk eat it too often to consider it out of the ordinary. The shells do
not go to waste either; they are used to decorate house exteriors, line garden
edges, serve as "gravel" walkways when crushed, and even cut and
polished into buttons and sequins to adorn gowns.